Geuze is blended, Lambic is brewed
Geuze is blended, not brewed. Geuze is created by combining several Lambic beers. Those Lambic beers, however, are brewed. Still with me? We are happy to show you all about the art of making Geuze.
Lambic is brewed with malt and wheat, but they are about the only things it has in common with other beers. Unlike other brewers, Lambic brewers do not add yeast to their brew. Lambic is made with a process referred to as spontaneous fermentation. All that is needed is the ambient air of the Zenne valley to work its magic on cold winter nights. This activates naturally occurring wild yeasts and bacteria in the brew, which is in an open cooling vessel.
Lambic we brew in the winter months is given ample time to mature in large oak barrels: our foeders. This allows the beer to continue to evolve thanks to the rich microculture living in these old oak barrels. Geuze is made by blending Lambic beers from different years – and therefore different foeders. Oude Geuze Boon for example, is a blend of Lambics that matured for 1, 2 and 3 years. That blend then undergoes several months of bottle conditioning, a second fermentation inside the bottle.